I would just add that if you're looking at this as a Linux system (you said you don't want to run Windows) just be sure you're aware of limitations you might bump up against compared with the Mac: e.g., you won't be able to deliver ProRes files (maybe not a problem in your case), and if you're also doing audio and need more than what Fairlight offers you could be setting yourself up for more complexity if you go with Linux.
If you do go with Linux, the simplest/most stable solution would probably be to download the CentOS image from Blackmagic Design (see this thread
viewtopic.php?f=21&t=70949) rather than trying to get Resolve to work in Ubuntu or another distro. People do run Resolve in Ubuntu, but there's a long thread here on the forum on the many issues and obstacles people encounter (
viewtopic.php?f=21&t=56878). Also look at the Resolve configuration guide for recommended configurations in Linux.
I agree that Mac prices are high these days, but buying refurbished levels the playing field a little. I saved nearly $1,000 on my Mac Pro by buying it refurbished, although even with that it was still pricier than a comparable Windows machine. And you might want to rethink your opposition to Windows too; plenty of people are using Resolve on Windows machines.
Resolve 18 Studio, Mac Pro 3.0 GHz 8-core, 32 gigs RAM, dual AMD D700 GPU.
Audio I/O: Sound Devices USBPre-2